Originally Posted by boatster
The urethane seems to win in the manufacture, weight, and strength dept according to that article. Very compelling argument, but with such a good reputation for hypalon only time or a good weathering test can determine how Urethane materials hold up.
Well they're are some companies out there that do use PU (polyurethane) for tube manufacture, mainly Tornado and XS-Ribs so a good weathering test would be to simply find an old Tornado and compare it to a similarly ageed hypalon RIB. You'll find that the PU tubes won't have faded as much and have kept their lustre. One thing I always notice about old Tornados is that I always get their age wrong because the tubes always look 4/5yrs newer.
Has been discussed many a time here before, see here:
Be aware that in a lot of these threads PU (polyurethane) has been confused with PVC (Poly Vinyl Chloride). PVC is actually more closely related to Polyethylene, and therefore Hypalon than PU.
The only similarity is that both fabrics can be heat welded. PVC is an unstable polymer because of the chemical make up of the fabrics coating.
This means that the PVC fabric is constantly changing, oxidizing and migrating to the surface. PVC's are liquefied with solvents where polyurethane is liquefied by heat, leading to a significantly more stable fabric coating. Stories about tubes rotting in the sun are about PVC - not polyurethane.